Patent GB-191416696-A (GB)
Title: Improvements in Railway Block Telegraph Signalling Apparatus.
Inventor: BRAIN ORLANDO WILLIAM
IPC: B61L23/12
Filed: 1914-07-13
Granted: 1915-07-13
Abstract: 16,696. Brain, O. W., and Hodgson, C. A. July 13. Signalling-instruments; slots, reversers, and like apparatus.-Signalling instruments have four signal-dials and plungers with one bell and two signal positions. In working a train, the dispatcher plunges at ' Bell,' and the receiver replies by plunging ' Line clear.' When the train has entered the section, the dispatcher plunges ' Train on line,' and after receiving a bell signal from the receiver that the train has arrived, the dispatcher plunges ' Train arrival acceptance.' Finally, when the train has passed over the exit treadle, the receiver plunges ' Line closed,' which returns the instruments to their original positions. Similar signals are shown simultaneously in the two instruments. The plungers have electric circuit commutators normally on open circuit and can be turned in one direction only. Each signal disk is turned step by step automatically by a magnet in the local circuit and is provided with a commutator which co-operates with the plunger commutator in the same instrument to control the line circuits, and co-operate with the track treadle devices to control the local circuits established by the relay in the line circuit. Bell signals are sent by currents of less strength than those for other signals. Separate polarized relays are used for incoming and outgoing currents, and these relays do not respond to bell signal currents. The incoming relay may be adapted to respond to the bell signal current sufficiently to close a bell circuit, but not sufficiently to close other local circuits; or a separate bell circuit relay may be placed in either the line circuit or that of the incoming relay. Fig. 26 shows the initial condition of the circuits. When the dispatcher with the instrument A plunges at ' Bell,' the plunger commutator connects contacts 6, 7 and contacts 2, 3; putting half the line battery in the line circuit, which passes through contact w, arm of dial commutator, outgoing relay 140 to line, incoming relay 140, and contacts 195, 127 in receiver's instrument B. The latter relay is thereupon operated, but only sufficiently to close the circuit of its bell 106. The plunger of instrument B is then turned to ' Line clear ' and plunged. This connects contacts 2, 3 and contacts 4, 5, which put the full line battery at B in circuit with the dial-commutator arm and contact y and the outgoing relay at B, and the incoming relay 140 and contacts 195, 127 at A. In the instrument B, the outgoing relay closes a circuit of the dial-actuating magnet 112 through contact Z and brings the dial to ' Line clear.' In the instrument A, the incoming relay rings the bell and closes the circuit of magnet 112 to bring the dial to ' Line clear ' through contact X. This circuit also includes the pick-up coil of a stick-magnet 160, by which the contacts 164, 165 of the signalcontrol circuit are bridged, and the coil of the magnet 121, by which a trip 123 is removed, permitting contacts 124, 126 to come together. Further, the plunger at B opens the spring contacts 120, 125 and 124, 126 at B, which are in the circuit at B required for the Line closed ' plunge, and these are then held open by trips 118, 123. Fig. 24 shows the signalcontrol circuit. When the contacts 164, 165 are bridged, the magnet 229 is energized and brings the armature 230 into position for acting as pivot for the floating lever 223. By pulling the wire 228, the signal may then be put to ' Safety.' When a train enters the section, the treadle 241 breaks the circuit of the magnet 229 at 242, a spring 231 removes the pivot armature 230, and the signal falls to ' Danger.' The train having entered the section, the dispatcher plunges 'Train on line' at A. This connects contacts 1, 2 and contacts 3, 4 by the plunger commutator at A, thereby closing a line circuit which passes through contacts 124, 126, dial-commutator contact x, and outgoing relay at A, and incoming relay and contacts 127, 195 at B. The local circuits thus closed pass through contact Y at A and contact W at B respectively, and cause the magnets 112 to move the dials to 'Train on line.' The plunger at A also breaks the signal-control circuit at 167, 168 and repeats the action of the track treadle. When the train arrives at the further end of the section, the commutator at B is plunged at 'Bell,' thereby connecting contacts 263 and contacts 6, 7. This puts half the line battery at B in circuit with the dial-commutator contact z and the outgoing relay at B, and the incoming relay and contacts 127, 195 at A, and the bell at A is rung. In response, the commutator at A is plunged at ' Train arrival acceptance.' This connects dial-commutator contacts 2, 3 and contacts 4, 5 and thereby closes a line circuit through dial-commutator contact y and outgoing relay at A, and contacts 195, 127 and incoming relay at B. The local circuits closed by the relays pass respectively through contact Z and magnet 112 at A and magnet 121, and contact X and magnet 112 at B, and the dials are moved to ' Train on line.' The plunge at A also opens the signalcontrol circuit at contacts 124, 126 at A. The energization of the magnet 121 at B removes the trip 123 and permits contacts 124, 126 at B to close. When the train passes out of the section, .it operates a treadle which bridges con. tacts 263, 264, and thereby a magnet 117 is energized, which removes the trip 118 and permits the contacts 120, 12.5 to close. The commutator at B is then plunged at ' Line closed ' and connects contacts 1, 2 and contacts 3, 4, by which a line circuit is made through contacts 120, 125, contacts 124, 126. dial-commutator contact x, and outgoing relay at B, and incoming relay and contacts 127, 195 at A. This closes local circuits which pass respectively through magnet 112 and dial-commutator contact Y at B and magnet 112 and dial-commutator contact W at A, and thereby the dials are brought to their initial positions showing ' Line closed.' Fig. 14 shows the extension 114 of the pivoted armature of the magnet 112 by which the dial is turned step by step. The upper shoulder of the part 208 engages the stops 202 in turn to rotate the disk, and the face of the part 208 engages with the faces 201 on the disk to lock the disk when the part 208 is in its upper extreme position. A tooth 211 engages the stops 202 and holds the disk when the part 208 is in its lower extreme position. In an alternative arrangement, the disk has one stop 202, and four magnets disposed around the disk act upon it in turn.